Cambridgeshire force works on one of the ‘most sickening crimes’ seen by a senior officer.

Police at the house on Magazine Lane in Wisbech. Picture: Matthew Usher.

Police have found a large knife as they hunt for the killer of Wisbech widow Una Crown.

A man delivering newspapers discovered the weapon in a street close to Magazine Lane this morning.

The knife has been seized and will be examined to see if it is linked to the murder of the 86-year-old.

Mrs Crown’s body was discovered in her bungalow at 10.45am on Sunday. She was last seen alive on Friday and had spoken to a friend by telephone at about 5pm on Saturday.

A post-mortem examination confirmed she died as a result of stab wounds to her neck and chest.

Her body was set on fire following her death in an apparent attempt to hide her injuries and destroy evidence.

Detective Chief Inspector Jon Hutchinson said: “We were made aware of the discovery of a knife in a street near to Magazine Lane this morning.

“The knife has been seized and we will be carrying out tests to see if it has any link to Mrs Crown’s murder. It is still very early and we are keeping an open mind as to the relevance of this discovery.

“We are continuing with searches of the area around Magazine Lane and house-to-house enquiries are ongoing.”

Officers will be stopping motorists, cyclists and walkers in the area over the weekend asking people whether they remember seeing anything suspicious last weekend.

DCI Hutchinson added: “We hope to jog people’s memories and would urge people to think back to what they were doing last weekend. Were you in the area of Magazine Lane? Did you see anyone acting suspiciously?

“Any information could prove to be vital in catching whoever is responsible for this terrible crime.”

Anyone with any information should call the Major Crime Unit on 101 or Crimestoppers, anonymously, on 0800 555111.